1. Field of the Invention
The present invention relates to hand grip instructional aids and, more particularly, to a device that indicates when a user is applying excessive pressure to a hand grip of a golf club, a tennis racket, or any number of other hand manipulated implements.
2. Description of the Prior Art
There are various sports which require an athlete to utilize a club or some other hand manipulated implement for swinging at a ball which is fixed at a stationary position in front of the athlete or else is rapidly advancing toward the athlete. An example of such a sport is golf, wherein the golfer utilizes a golf club to drive a stationary golf ball that is positioned either on a golf tee or on the ground in front of him. In other sports, such as tennis or baseball, the athlete utilizes a tennis racket or a baseball bat, respectively, for swinging at a rapidly approaching ball. In all of the above mentioned sports, and numerous others, it has been found that the athlete's grip on the associated athletic club plays an important role in the final direction and control of the ball.
To assist an athlete in developing a proper grip on an athletic club or other hand manipulated implement, several inventive efforts have been made. For example, U.S. Pat. Nos. 4,930,785, 4,103,896, 4,138,118, 3,897,058, 4,861,034 and 4,027,879, all address various methods of assisting an athlete in developing a proper grip. A brief description of these prior art devices is now given.
U.S. Pat. No. 4,930,785 (Mills) discloses a golf grip handle incorporating a battery operated electrical circuit that is activated in response to excessive grip pressure at a particular point along the handle. The electrical circuit is connected to a motor that produces vibrations in the handle so as to alert the user of the excessive grip pressure.
U.S. Pat. No. 4,103,896 (Lorang) discloses a golf club handle which includes a switch to be placed under the middle fingers of one of the user's hands to provide an output signal if excessive pressure is applied by those fingers. Typically, the switch is placed under the middle finger of the user's right hand to sense excessive pressure and to provide an output signal as a result of the excessive pressure.
U.S. Pat. No. 4,138,118 (Budney) discloses a strain gauge on a handle of a golf club to sense an applied pressure of a user's fingers on the handle. A plurality of strain gauges may be placed axially on the handle so that the pressure of the fingers at several locations on the handle may be sensed. The strain gauge(s) are connected to a pen recorder to record the output of the gauge(s) continuously during the user's golf swing. The apparatus requires a cord extending from the handle to the pen recorder which may be distracting to the user.
U.S. Pat. No. 3,897,058 (Koch) discloses a training aid apparatus for achieving a correct grip on a golf club, tennis racket, baseball bat, etc., that requires a pressure responsive grip. The apparatus includes a hollow handle connected to a pressure gauge so that the force of the user's hands can be sensed. The sensed pressure is remote from the user, and accordingly there is no sensation or output indication to the used while he or she is swinging. An instructor apparently observes the output pressure. Since the sensing is remote, the handle being gripped is connected to the pressure gauge by a cord, which may be distracting to the user.
U.S. Pat. No. 4,861,034 (Lee) discloses a golf grip training device that may be installed on a conventional golf club. The device includes an elongated pressure sensitive switch that is mounted to the underside of the golf club handle and that is responsive to a user's grip pressure. The switch is connected to a signalling device that is further mounted to the golf club which emits an audible signal when a predetermined grip pressure is exceeded.
U.S. Pat. No. 4,027,879 (Wright) discloses a tennis racket grip training device which operates upon a form of translation of pressure, whereby an excessive application of pressure to the tennis racket handle causes a partial disengagement of the handle from its connecting shaft, thereby producing both a visible and an audible indication of an improper hand grip.
Although all of the above-mentioned prior art devices provide various methods of assisting an athlete in developing a proper grip, none propose a device having a specific handle construction comprised of a conductive splined core, a deformable material disposed annularly around the splined core, and a conductive material disposed in a further annular relation around the deformable material so as to allow any portion of a user's grip on the handle to be sensed for excessive applied pressure by way of an electrical contact being made between the conductive splined core and the conductive material and to provide a user detectable indication thereof. Such a device would be desirable for training in the sports of golf, tennis, baseball, and numerous others where an athlete's grip plays an important role in his or her performance. It is therefore desirable to provide such a device and to overcome the shortcomings of the above-mentioned prior art devices in this area.